They could set up a playoff and have a very rigid entry requirement — CONFERENCE CHAMPIONS ONLY!
Right now there are 11 conferences, these could easily be consolidated down into 8 conferences — indeed some of the smaller ones are looking at combining already.
BY combining and making larger conferences you force a Conference Championship game. The champions then enter the playoff, and everyone else is available for bowl games just as they are now.
With an 8 team playoff of conf champs and the conf champ games you end up with a defacto 16 team playoff.
QED!
BTW..see my #13,,good read..